@The_Next_Rex
The problem with your blog is you are using too many external scripts (Amazon, Add this & few more)… No matter what you do, your blog loading will be little higher than sites who are not using too many external scripts.

I would suggest to focus on bringing your loading time to 2-3 seconds top. Here are few suggestions:

Use WP Supercache plugin

Use Cloudflare as it offers free CDN, rocketloader & many other great features.

I can’t help you much on enabling compression or minifying JavaScript, HTML or CSS but I’ll surely recommend you to use OPTIMIZILLA image compression tool to optimize your images. Its a great tool, I use it regularly. Optimizing images will really help in improving your PageSpeed Score.

aglasem.com has page load time of 2.9 seconds still alexa says that 86% sites are faster then it. On the basis of it can say that yes you should improve more. Now comming to your previous question: Yes you have to reduce the size of your pics but you don’t want to loose their quality, right? For that optimizilla provide you quick option to tweak or you can say set the quality of the image on your own and you can see the live preview and different in quality between the original pic and optimized one at the same time. I found the tool very helpfull.